PPT ON BASICS OF NC TECHNOLOGY BASED ON THE MECH.ENGG SYLLABUS

1. NC TECHNOLOGY

3. The first NC machines were built in the 1940s and '50s.

5. SIEMENS CNC PANEL

6. ` BASIC COMPONENTS OF NC SYSTEM PROGRAM OF INTRUCTIONS MACHINE CONTROL UNIT MACHINE TOOL OR OTHER CONTROLLED PROCESS.

7. It is the detailed step-by step set of directions which tells the machine tool what to do. It is coded in numerical or symbolic form on some type of input medium that can be interpreted by the controller unit. The most common input medium today is 1-inch wide. Input method can be manual or by means of direct link with a computer , called direct numerical control or DNC. PROGRAM OF INTRUSTIONS

8. . SPROCKET HOLES PUNCHED TAPE PROGRAM OF INTRUCTIONS

9. MACHINE TOOL It is part of the NC system which performs useful work. It includes the cutting tools, work fixtures, and other auxiliary equipment needed in the machining operation..

10. THE NC PROCEDURE PROCESS PLANNING PART PROGRAMMING TAPE PREPARETION & VERIFICATION PRODUCTION

11. PROCESS PLANNING This step is referred to as process planning and it is concerned with preparation of route sheet. The route sheet is a listing of the sequence of operations which must be performed on the work part.

12. PART PROGRAMMING Part programmer plans the process for the portions of the job to be accomplished by NC. They are responsible for planning the sequence of machining steps to be performed by NC and to document these in a special form.

13. TAPE PREPATION AND VERIFICATION A punched a tape is prepared from the part programmer’s NC process plan. After the tape has been prepared, a method is usually provided for checking the accuracy of the tape The “Acid Test” of the tape involves trying it in and out on the machine tool to make the part. A foam or a plastic material is sometimes used off this tryout.

14. PRODUCTION The final step in the NC procedure is to use NC tape in production. This involves ordering the raw work parts, specifying and preparing the tooling and any specific fixturing that any be required and setting up the NC machine tool for the job. When the part is completed the operator removes it from the machine and loads the next.

15. NC CO-ORDINATE SYSTEM The purpose of cordinate system is to provide a means of locating the tool in relation to the workpiece. Depending on the NC machine, the part programmer may have several differnet options avalable for specfying this loaction.

16. z y -x x Machine table -y -z

17. NC MOTION CONTROL SYSTEM point-to-point Straight – cut CONTOURING NC

18. tool workpiece Point to Point

19. Cnc drill workpiece

20. tool workpiece STRAIGHT CUT

21. CONTOURING

22. CONTOUR MADE BY A CNC MACHINE ON FOAM

23. APPLICATIONS OF NUMERICAL CONTROL MOST WIDELY USED IN METAL CUTTING INDUSTRIES MILLING DRILLING,BORING,TURNING ,GRINDING AND SAWINGAND RELATED PROCESS.

24. APPLICATIONS OF NUMERICAL CONTROL In addition to metal machining, numerical control has been applied to a variety of other operations.. Press working machine tools,Clothcutting,Automaticriveting,Wire-wrap machines,Welding machines, Inspection machines,Automatic drafting.

25. ADVANTAGES Reduced non-productive time. Reduced fixturing. Reduced manufacturing lead time. Greater manufacturing flexibility. Improved quality control.

26. DISADVANTAGES Higher investment cost. Higher maintenance cost. Finding and/or training NC personal